Guard for electric-railway trolleys



(No Model.) 2 Sheets-Sheet 1. H E. THOMSON. GUARD FOR ELBGT'RIG RAILWAY TROLLBYS.

Patented Apr. 15, 1890.

WITNESSES: l nvmvron A TTORfJEY.

(No Model.) 2 Sheets-Sheet 2.

E. THOMSON.

I GUARD FOR ELECTRIC RAILWAY TROLLEYS. No. 425,640. PatntedApr. 15, 1890.

WLTUE 5 5 E 5. F1 g. 4-. I Inv E1111] 1 W M W UNITED I STATES PATENT FFICE.

ELIIIU THOMSON, OF LYNN, MASSACHUSETTS, ASSIGNOR TO THE THOMSON- IIOUSTON ELECTRIC COMPANY, OF CONNECTICUT.

GUARD FOR ELECTRIC-RAILWAY TROLLEYS.

SPECIFICATION forming part of Letters Patent No. 425,640, dated April 1890.

Application filed February 10, 1890- Serial No. 339,873. (No model.)

To all whom it may concern:

Be it known that I, ELIHU THOMSON, a cititermed, provided at its outer extremity with a grooved contact device passing along the conductor.

My invention consists in attaching to the outer end of the trolley-pole a frame or guard around the trolley-wheel or contact device, by which, in case of derailment of the said contact device it will be impossible for the outer end of the trolley-pole to be thrown up beyond the conductor so as to interrupt the circuit and interfere with the cross suspension-wires,

My invention is illustrated in the accompanying drawings, in which- Figure 1 is a perspective view showing the outer end of an ordinary trolley-pole with its contact-wheel and the line-conductor against which it is adapted to bear. Figs. 2, 3, and 4 show the electrical connection from the guard to the lamps and motor on the vehicle.

Referring to the drawings, A is a trolleypole, either of wood or of metal, carrying at its outer extremity a grooved contact-wheel B. C is a suspended line -conductor, along which the wheel B is adapted to travel.

D is an insulator supporting the conductor C, and it is itself supported by a transverse suspension-wire E.

To the end of the trolley-pole is attached a triangular frame or guard F. At its lower end it is clamped to the trolley-pole by bands G or by any other suitable means of attachment. It is provided with a transverse brace H, and at the outer end the two wires. are turned down and connected by a transverse piece K. By this construction the end of the guard is somewhat below the trolleywvheel and behind it, so that whenever by any chance the .wheel 13 is derailed and the spring which normally holds the wheel up against the wire tends to throw it up past the conductor the guard will strike the conductor C and prevent the wheel B rising far enough to interfere with the cross suspension-wire E. It will also permit of the wheel being readily restored to its normal position, as the latter is not permitted either to rise beyond the conductor C or swing to one side away from it.

In addition to the mechanical advantages of this device, it has also an important electrical f unctionviz., to maintain the current through the motor, or at least through the lamps of the car, which without provision of this kind would be extinguished. This latter function is of special importance,

as the extinguishment of the lights is a source of annoyance and alarm to the passengers, and at the same time prevents the replacing of the trolley at night without considerable difficulty and delay. To perform its electrical function, the guard may either be in electrical connection with the metal of the trolley-pole or, if a wooden pole is used, with a conductor leading from the trolley-wheel; or it may, on the other hand, be insulated from the trolley and be provided with a separate wire leading to the vehicle. In the latter case there are several ways in which the lamps may be disconnected from the main trolley-conductor and connected to the guard or supplementary conductor whenever the circuit of the former is interrupted by reason of the trolley getting 8 5 off from the main conductor. A number of these methods are illustrated in Figs. 2, 3, and 4.

In Fig. 2 the guard G is provided with a supplementary conductor L, leading down to the magnet M and thence to the opposite side of the circuit. The magnet will be of considerable resistance and will become energized when the guard comes into contact with the main conductor. \Vhen this occurs the armature of the magnet will be attracted, and the normal circuit through the lamps O and by the armature to contact-point P and the main trolley=conductor will be interrupted and a new circuit established from the lamps O by too the armature to contact-points N, to the wires L, to the guard, and the conductor. By this arrangement thelamps will be in circuit whenever the guard comes against the main conductor.

In Fig. 3 there is shown an arrangement by which the interruption of the main line causes the magnet M to release its armature and throw the circuit of the lamps from the main In Fig. 4 an additional set of lamps S is employed and placed in circuit with a resistance R connected to the guard. One-half of the principal lamps 0 will alsobe included in multiple arc with the group S. In this arrangement no magnets will be employed.

One advantage of having the guard insuas described, is that a derailment of the trol-l ley will be noticed by the driver, although the; lamps are not extinguished, and the guard willnot be permitted to travel a long distance; against the line-wire, performing the f one-1 tions of the trolley-wheel,which to a certain extent it. isadapted to do, having the turnedover sides, which correspond to the flanges of1 thewheel in preventing lateral displaeem cut.

I do not intend to limit myself to the exacti form of guard shown, in which it is composed of thetwo laterally-diverging side wire arms, turned over at their outer ends and connected by a transversepiece exten din g across the line-* conductor; but I desire it to be understood that I may employ any equ ivalentperformingthe samefunctions as the device specifically set forth.

What I claim as new, and desire to secure by Letters Patent, isv 1. The combination, with a traveling con tact held in connection with a line-wire, of a guard connected thereto and extending across. the line-wire, so as to engage with said wire in case of derailment of the contact device.

2. The combination, with an electric-railway trolley, of a guard having its sides turned over to prevent lateral displacement when it engages the line-wire upon derailment of the trolley.

3. The combination, with .an electric-railway trolley, of a guard consisting of a wire frame having two arms diverging laterally on trolley-wire to the supplementary guard-Wire.

lated and provided with a separate conductor. L

opposite sides of the trolley-wheel, the ends of the arms being turned over and connected by a transverse piece extending across the linewire.

Way trolley adapted to trail along a conducting-Wire, of a guard extending behind it and outof the line of the said wire, so as to engage therewith in case of derailment of the trolley.

5. The combination, with an electric-railway-trolley, of a guard of conducting material attached thereto and extending across the linewire, so as to engage therewith in case of derailment of the contact device, and thus preserve the electrical connection with the vehicle.

6. The Icombination, with a traveling contact device attached to a vehicle and held in connection with a line-wire, of a guard connected thereto and insulated therefrom, and an insulated conductorleading from the guard to the vehicle.

7. The combination, \vitha contactdevice connectedto a vehicle and pressed against a line-wi re, of an insulated guard, a linetherefromto the vehicle, a set of lamps onthc vehicle, and a circuit-changer for shiftingthe lamp-circuit from the contact device to the guard as one or the other is in contact with the line-wire.

4. The combinatiomwith an electric-rail- 8. The combination,with an electric-railway trolley, of a guard insulated therefrom, a conductor leading to the vehicle, a-set of lamps onthe vehicle, a circuit-changer for the lamp-circuit, and an electro-magnet controlling said circuit-changer to maintain thelamps always in circuit.

9. The combination, with an electric-railway trolley, of a guard insulated therefrom, a conductor leading from the guard to the vehicle, a set of lamps on the vehicle, a circuitchanger for the lamp-circuit, and a controlling-magnet for said circuit-changer in the trolley-connection, whereby the interruption of contact between thetrolley and the linewire shifts the lamp-circuit to the guard.

In witness whereof I have hereunto set my hand this 6th day of February, 1890.

ELIHU THOMSON. Witnesses:

JOHN W. GIBBONEY, DUGALD MCKILLOP. 

